Set option default for enabling memory ssa for new pass manager loop sink pass to true.

Summary:
Set the default for the option enabling memory ssa use in the loop sink
pass to true for the new pass manager.
Author: Jamie Schmeiser <[email protected]>
Reviewed By: asbirlea (Alina Sbirlea)
Differential Revision: https://reviews.llvm.org/D92486

Author: jamieschmeiser

llvm/lib/Transforms/Scalar/LoopSink.cpp

@@ -70,7 +70,7 @@ static cl::opt<unsigned> MaxNumberOfUseBBsForSinking(
     cl::desc("Do not sink instructions that have too many uses."));
 
 static cl::opt<bool> EnableMSSAInLoopSink(
-    "enable-mssa-in-loop-sink", cl::Hidden, cl::init(false),
+    "enable-mssa-in-loop-sink", cl::Hidden, cl::init(true),
     cl::desc("Enable MemorySSA for LoopSink in new pass manager"));
 
 static cl::opt<bool> EnableMSSAInLegacyLoopSink(